Load test system

ABSTRACT

A load test system performs a load test of an emergency generator. The load test system includes a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from an emergency generator is inputted, and a storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted at an input voltage being set to substantially the same value as or lower than the output voltage.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of International Patent Application No. PCT/JP2017/014678 filed on Apr. 10, 2017, which claims priority to Japanese Patent Application No. JP2016-233031 filed on Nov. 30, 2016, the entire contents of which are incorporated by reference.

TECHNICAL FIELD

The present invention relates to a load test system having a load resistor for a load test of an emergency generator or the like.

BACKGROUND ART

Among conventional load test apparatuses, there has been known a so-called dry load test apparatus capable of performing a load test in response to the output of a power source of a generator or the like by selectively switching connection conditions of serial connection and/or parallel connection of a plurality of load resistors (see Patent Literature 1).

CITATION LIST Patent Literature

Patent Literature 1: JP 2010-25752 A

SUMMARY OF INVENTION Technical Problem

However, conventionally, power purified by an operation test, that is, a load test of an emergency generator or the like is turned into thermal energy as a load resistance and then consumed, so that the power energy has been wasted.

It is therefore an object of the present invention to provide a load test system capable of reducing the power energy wastefully consumed in the operation test, that is, the load test of the emergency generator or the like.

Solution to Problem

The load test system of the present invention is

a load test system for performing a load test of an emergency generator,

the load test system including:

a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from an emergency generator is inputted; and a storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted at an input voltage being set to substantially the same value as or lower than the output voltage,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from an emergency generator is inputted; a storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted at an input voltage being set to substantially the same value as or lower than the output voltage; and a load resistor to which AC power generated from the emergency generator is inputted, in which

the load resistor has a dry-type resistor unit for converting the inputted AC power into thermal energy,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from an emergency generator is inputted; a storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted at an input voltage being set to substantially the same value as or lower than the output voltage; a DC/AC converter for converting DC power from the storage battery into AC power; and an operating power source of a load resistor to which AC power converted by the DC/AC converter is inputted, in which

the load resistor has a dry-type resistor unit for converting the inputted AC power into thermal energy,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

an operating power source for driving an emergency generator; a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from an emergency generator is inputted; a storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted at an input voltage being set to substantially the same value as or lower than the output voltage; a DC/AC converter for converting DC power from the storage battery into AC power; and an operating power source of a load resistor to which AC power converted by the DC/AC converter is inputted, in which

the load resistor has a dry-type resistor unit for converting the inputted AC power into thermal energy,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

an operating power source for driving an emergency generator; a changeover switch to which AC power from the emergency generator is inputted; an AC/DC converter being connected to a first switch section of the changeover switch, to which AC power generated from the emergency generator is inputted; a plurality of secondary battery charging elements to which DC power converted by the AC/DC converter is supplied; and a load resistor being switched to be connected to a second switch section of the changeover switch, to which AC power from the emergency generator is inputted to convert the AC power into thermal energy, in which

the secondary battery charging elements are formed by connecting a plurality of secondary batteries in series and/or in parallel, and are able to correspond to plural kinds of emergency generators having different power generation capacities,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

an operating power source for driving a three-phase alternating current emergency generator; a changeover switch to which AC power from the three-phase alternating current emergency generator is inputted; an AC/DC converter being connected to a first switch section of the changeover switch, to which power from the emergency generator is inputted; a plurality of secondary battery charging elements to which DC power converted by the AC/DC converter is supplied; and a load resistor being switched to be connected to a second switch section of the changeover switch and being formed with a dry-type resistor unit for converting the inputted power into thermal energy, in which

the secondary battery charging elements are formed by connecting a plurality of secondary batteries in series and/or in parallel, and are able to correspond to plural kinds of three-phase alternating current emergency generators having different power generation capacities, and

the plurality of secondary batteries have a generally square shape, a size of approximately 100 cm in width, approximately 70 cm in length, a thickness in a range of approximately 2 cm to 4 cm, and a weight in a range of approximately 100 g to 300 g,

or

a load test system for performing a load test of an emergency generator,

the load test system including:

an operating power source used at the time of driving a three-phase alternating current emergency generator; a changeover switch to which AC power from the three-phase alternating current emergency generator is supplied via a power input section; an AC/DC converter being connected to a first switch section of the changeover switch, to which AC power from the emergency generator is inputted; a plurality of secondary battery charging elements to which DC power converted by the AC/DC converter is inputted; and a load resistor being switched to be connected to a second switch section of the changeover switch and being formed with a dry-type resistor unit for converting the inputted AC power into thermal energy, in which

the secondary battery charging elements are formed by connecting a plurality of capacitor secondary batteries in series and/or in parallel, and are able to correspond to plural kinds of three-phase alternating current emergency generators having different power generation capacities,

or

the chargers having the AC/DC conversion function and the storage battery can be installed in an electric vehicle, and the power source of the electric vehicle can be inputted from the charged storage battery,

or

the secondary battery charging elements can be installed in an electric vehicle, and the power source of the electric vehicle can be inputted from the charged secondary battery charging elements,

or

the operating power source at the time of driving the load resistor is inputted from power charged in the load test system,

or

the operating power source at the time of driving the emergency generator is inputted from power charged in the load test system.

Advantageous Effects of Invention

The present invention exhibits an excellent effect that the power energy wastefully consumed by a load test can be reduced.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an arrangement (1) illustrating a load test system according to the present invention.

FIG. 2 is an arrangement (2) illustrating a load test system according to the present invention.

FIG. 3 is an arrangement (3) illustrating a load test system according to the present invention.

FIG. 4 is a cross-sectional view illustrating an arrangement of a capacitor secondary battery unit according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment

FIG. 1 illustrates an arrangement of an embodiment.

A reference numeral 1 indicates an emergency generator. The emergency generator 1 can be a three-phase alternating current emergency generator 1 capable of generating and transmitting, for example, a power capacity of 100 kW at a voltage of 200 V. However, it is not limited to the emergency generator 1 conforming to the above-mentioned specifications.

Such emergency generator 1 is permanently installed in facilities such as commercial buildings, but when a need arises to urgently use the generator, for example, when a sudden power failure occurs, the generator must be able to be immediately started for use. If the generator cannot be immediately stated for use, it is useless permanently installing it.

Therefore, the emergency generator 1 requires an operation test periodically. That is, the operation test called a load test, of the emergency generator needs to be periodically performed.

For one example of the operation test, that is the load test, a power generation test (load test) can be exemplified, in which the emergency generator 1 is continuously operated for approximately 30 minutes to 1 hour, and it is then confirmed whether or not abnormality is present in the power generation operation, more specifically, the emergency generator 1 having a capacity of 100 kW as described above is operated by one third of the capacity, for example, at approximately 34 kW power, for approximately 1 hour and it is confirmed whether or not the emergency generator 1 can normally and stably generate power and transmit it. A test is also included in which the emergency generator 1 is turned on/off several times to determine the presence or absence of abnormality.

Here, in a normal power generation test, that is, a load test, of the emergency generator 1, it is preferable that a load (room air conditioner, lighting appliance, elevator, power source for operation, etc.) connected to the emergency generator is actually driven and a test is then performed whether or not a high loading condition can be maintained, but is difficult in practice. Therefore, a load test is performed by connecting a so-called simulated load to load the emergency generator.

To start the emergency generator 1, a power supply by an operating power source generated by, for example, a control power source from a DC power source unit, a starter type power source from a battery, an air-start type power source started by storing air, or the like is required.

When a power generation apparatus such as the emergency generator 1 loses a DC power source for controlling, it no longer operates.

Currently, a DC power source unit for starting set with the emergency generator 1 obtains power from a commercial power source, converts the commercial power source into DC with an AC/DC converter to charge a battery, and then starts a power generation apparatus such as the emergency generator 1 to be used in an emergency such as at power failure.

However, even though the commercial power source is lost, it does not matter as long as the power remains in the battery, but when the power charged in the battery is lost, the emergency generator 1 no longer starts.

Then, in order to drive the emergency generator 1 without any trouble even in the event of a disaster, an emergency, or any situation, the emergency generator 1 requires an arrangement such that power supplied not only from a commercial power source but somewhere, for example, power generated at the load test system, is supplied to the DC power source unit for starting.

Therefore, in the present invention, the operating power source for driving the emergency generator 1 is not received from another external power source (commercial power source) alone but uses power generated to perform a load test at the emergency generator 1, and further, an operating power source of a load test apparatus for driving the load test apparatus is also not received from the commercial power source but uses power suppliable from somewhere, for example, power generated in order to perform a load test with the emergency generator 1.

Conventionally, as the simulated load, a “water load test apparatus” for applying a load by boiling water, a “dry test apparatus” using a rod-shaped heating resistor body like a so-called nichrome wire, or the like has been used. However, the load test system of the present invention adopts an arrangement completely different from the conventional load test apparatuses, the arrangement that does not waste power generated by the load test.

Therefore, the arrangement of the first embodiment of the load test system according to the present invention is shown in FIG. 1.

First, the emergency generator 1 is connected, via a changeover switch 2, to a plurality of chargers 21 . . . having an AC/DC conversion function that are connected in parallel, to which AC power generated from the emergency generator 1 is inputted.

As understood from FIG. 1, DC power from another power generation apparatus 22 such as a solar panel may also be connected in parallel to the output side together with the plurality of chargers 21 . . . having the AC/DC conversion function.

In addition, it is configured that connections are established between the emergency generator 1 and the plurality of chargers 21 . . . having the AC/DC conversion function that are connected in parallel via capacity changing switches 25, and the charging capacity can be changed by switching the capacity changing switches 25.

A reference numeral 23 indicates an operating power source for driving the emergency generator 1. Input power of the operating power source 23 will be described later.

Here, AC power generated from the emergency generator 1 is inputted to the plurality of chargers 21 having the AC/DC conversion function that are connected in parallel, or nine chargers 21 having the AC/DC conversion function in this embodiment.

Then, the AC power inputted to the plurality of chargers 21 having the AC/DC conversion function of which each charging capacity is set to, for example, 4 kW is converted into DC and is transmitted to the side of a storage battery 24 such as a lithium ion battery at a predetermined output voltage, for example, an output voltage set to 48 V, to thereby be inputted.

Here, the input voltage of the storage battery 24 is set to substantially the same voltage as the above-mentioned output voltage of the plurality of chargers 21 having the AC/DC conversion function that are connected in parallel, or to a voltage lower than the above-mentioned output voltage, and the charging capacity thereof is set to approximately 34 kW.

Therefore, the AC power generated at the emergency generator 1 is converted into DC by the chargers 21 having the AC/DC conversion function and is transmitted to the side of the storage battery 24 to be charged.

However, the load test of the emergency generator 1 is performed by increasing loads in the following manner. When the emergency generator 1 to be tested has a power generation capacity of 100 kW, one third of the capacity, that is, a generated power of 34 kW, is not loaded in one step, but the power is divided into four levels of power generation capacity and is then outputted with each level of capacity. Therefore, in the first step, a power generation capacity of approximately 9 kW is prepared and the approximately 9 kW of the generated power is outputted as a load.

At this time, it is necessary to connect three chargers 21 having the AC/DC conversion function to allow the charger to have a charging capacity of 12 kW, and then input the generated power from the emergency generator 1.

Next, the second step is to increase the load capacity to 17 kW and then perform a load test. In this case, five chargers 21 having the AC/DC conversion function are connected to set the entire charging capacity to 20 kW.

Further, in the third step, a load of 26 kW is applied. Therefore, seven chargers 21 having the AC/DC conversion function are connected to set the charging capacity to 28 kW, and a load test is then performed.

Finally, a test of applying a load of 34 kW is performed. That is, the emergency generator 1 having a capacity of 100 kW transmits approximately 34 kW power, which is approximately one third of the power generation capacity, to thereby apply a load. In this case, nine chargers 21 having the AC/DC conversion function are connected to set the charging capacity to 36 kW, and a load test is then performed. For these controls, a control unit is provided and is configured to allow detailed control.

Then, when there is no abnormality in the action of the emergency generator 1 during the load test described above, the load test is successfully completed.

Here, in the conventional load test, all the power generated by the emergency generator 1 has been consumed as thermal energy. In the present invention, however, the generated power can be effectively used.

More specifically, the plurality of chargers 21 having the AC/DC conversion function allow the AC power tentatively generated for the load test of the emergency generator 1 to be charged in the storage battery 24. When this storage battery 24 has a power capacity of, for example, 36 kW, it can be completely charged in approximately 30 minutes to 1 hour by the above-mentioned load test.

Further, as shown in FIG. 1, a DC/AC converter 26 is connected to the output side of the storage battery 24, and operation power, for example, power for driving a cooling fan to cool a hot resistor, can be supplied to an operating power source 27 of a load resistor 6 via the DC/AC converter 26. In addition, the operation power is also configured to allow to be supplied to the above-mentioned operating power source 23 of the emergency generator 1 by switching an operating power source changeover switch 28. Such control can also be performed at the control unit.

In FIG. 1, it is configured that the generated power from the emergency generator 1 can also be transmitted to the conventional-type load resistor 6 to perform the load test. Therefore, for example, after full charging of the storage battery 24 is completed, the changeover switch 2 is temporarily switched, and the load test may be performed using the conventional-type load resistor 6.

In the arrangement of FIG. 1, the control unit controls the changeover switch 2 to be previously switched to the side of the plurality of chargers 21 having AC/DC conversion function that are connected in parallel, and the storage battery 24 is preferentially charged with the power generated by the load test.

When the storage battery 24 reaches a fully charged state, for example, a detector detects the state and the control unit then controls the changeover switch 2 to be automatically switched to the side of the conventional-type load resistor 6.

Second Embodiment

Next, FIG. 2 illustrates an example of an arrangement of a second embodiment.

FIG. 2 is an embodiment having an arrangement of connecting to a plurality of secondary battery charging elements 3 via an AC/DC converter 4.

Here, the emergency generator 1 in this embodiment is a generator 1 that generates and transmits three-phase AC power, and is configured such that the changeover switch 2 is first preferentially switched to the side of the secondary battery charging elements 3 by a control unit 16 beforehand, and is then connected from a power input section 7 of the emergency generator 1 to the side of the plurality of secondary battery charging elements 3, so that an operation test, that is, a load test is performed.

It should be noted that three secondary battery charging elements 3 connected here are charged with DC power. Therefore, it is necessary to convert AC into DC by interposing the AC/DC converter 4 between the emergency generator 1 and the secondary battery charging elements 3.

As described above, the changeover switch 2 is preferentially switched to the side of the three secondary battery charging elements 3, and the three-phase AC power is transmitted from a first switch section 8 thus preferentially switched, to the AC/DC converter 4.

The DC power converted by the AC/DC converter 4 is supplied to three secondary battery charging elements 3 that are connected with the AC/DC converter 4. Then, the three secondary battery charging elements 3 charge and store a generated power to be used in the operation test, that is, the load test, of the emergency generator 1 without wasting the generated power.

Switch sections 18 are provided on the input side of the three secondary battery charging elements 3, and the three-phase alternating current is connected per phase to each of the secondary battery charging elements 3 via the corresponding switch sections 18.

Further, for example, in the case where the charging times of the three secondary battery charging elements 3 are slightly different from one another, the corresponding switch section 18 is opened/closed to allow the three secondary battery charging elements 3 to be individually attached/detached. These switch sections 18 are configured as a changeover switch unit 19 to perform the switching control by the control unit 16.

Here, the secondary battery charging elements 3 cannot be formed by connecting a plurality of lithium ion batteries in serial or in parallel. When a plurality of lithium ion batteries are used in serial or parallel connection, high heat is generated to thereby increase the possibility of igniting the batteries. Moreover, when the lithium ion batteries are connected in serial or in parallel, it is difficult to adjust the lithium ion batteries, such as maintaining voltage balance of the respective lithium ion batteries. Therefore, in order to prevent it, a complicated protection circuit needs to be formed.

Therefore, after completion of charging, once the secondary battery charging elements 3 thus interrelated are disconnected from the connecting, the circuits in the secondary battery charging elements 3 formed of lithium ion batteries need to be reestablished. That is, it is necessary to perform adjustment such as voltage adjustment again. Therefore, it is not suitable to use lithium ion batteries for the formation of the secondary battery charging elements.

As a battery for the secondary battery, a dry battery using nickel or the like is generally available. Although it is considered that a large number of the dry batteries are disposed to form the secondary battery charging elements, the dry battery for the secondary battery has a small capacity and is heavy in weight relative to the capacity. Therefore, it is also not suitable for the present invention to use the dry battery for the secondary battery.

Thus, it is considered that a secondary battery using a capacitor is used to form the secondary battery charging element 3. Currently, a secondary battery using a capacitor has been developed as much as possible, and the secondary battery charging element 3 formed using the capacitor can be easily connected in serial or in parallel when a large capacity circuit of the secondary battery charging element 3 is established, and no complicated protection circuit is required. In addition, there is little possibility of igniting the secondary battery charging element 3. Further, after charging of the secondary battery charging elements 3 is completed, the secondary battery charging elements 3 are detached from the load test system and new capacitor secondary battery charging elements 3 are then connected. Even so, it is not necessary to perform adjustment, so-called voltage adjustment, like the secondary battery charging element formed with lithium ion batteries.

Here, to provide explanation of the secondary battery using a capacitor, for example, a capacitor battery uses an electric double layer state as a replacement of a dielectric, the state being formed on interfaces between electrodes 9, 10 having a square flat shape and an electrolytic solution 11.

Usually, an electric double layer capacitor includes a positive electrode 9, a negative electrode 10, an electrolytic solution 11, and a separator 12 for preventing short circuit of the electrodes opposed to each other. Further, the exterior thereof is covered with a covering material 13 formed of resin film or the like, and a capacitor battery unit 14 having, for example, specifications of 4 V, 1 A/h and a generally square, flat shape is formed (see FIG. 4).

The size thereof is approximately 100 cm in width, approximately 70 cm in length, and in the range of approximately 2 cm to 3 cm in thickness, and the weight thereof is approximately in the range of 100 g to 200 g.

Then, a plurality of the capacitor battery units 14, for example, approximately 40 capacitor battery units 14 are connected in series to form a capacitor secondary battery charging element 3 having a capacity of approximately 8 kWh.

Moreover, the secondary battery 3 using this capacitor generates extremely small amount of heat, and does not require a complicated protection circuit to be disposed when connected in series or in parallel.

Thus, the secondary battery 3 using a capacitor can be formed as a capacitor secondary battery charging element 3 having a capacity of approximately 8 kWh by connecting a plurality of capacitor battery units 14 in series without separately requiring a protection circuit.

The capacitor secondary battery charging element 3 is formed so as to have a charging capacity of 8 kWh as a whole, but not limited thereto. A capacitor secondary battery charging element 3 having a charging capacity flexibly changed can be formed by changing several of the capacitor battery units 14 and connecting them in series or in parallel.

In FIG. 2, three secondary battery charging elements 3 are connected in which the capacitor battery units 14 based on the above-mentioned specifications are connected as described above.

Here, when the emergency generator 1 is driven, AC power at a voltage of 200 V is generated from the emergency generator 1. Then, the generated AC power is converted from AC to DC by the AC/DC converter 4 that is connected to the side where three-phase AC power is transmitted, and the capacitor secondary battery charging elements 3 connected to the AC/DC converter 4 are charged with the DC power. Thus, a load test of the emergency generator 1 is performed, and the generated power can be charged and stored in the capacitor secondary battery charging elements 3 without wasting the generated power.

Here, the secondary battery using a capacitor is almost instantaneously charged and has an extremely small internal resistance, so that the amount of heat generated by electrical resistance is extremely small. For example, at approximately one hour after starting of the load test, each of the capacitor secondary battery charging elements 3 reaches a fully charged state. One capacitor secondary battery charging element 3 having a capacity of 8 kWh, and three capacitor secondary battery charging elements 3 having a total capacity of approximately 24 kWh are charged with DC power, which is stored.

When the three capacitor secondary battery charging elements 3, and a battery charging element 20 connected to a quick charger 17 optionally mounted reach fully charged states, a full-charge detector 5 connected to the side of the capacitor secondary battery charging elements 3 detects their fully charged states and then reports the detection with an alarm signal. It should be noted that the alarm signal includes sound, light, and the like.

However, the test of the emergency generator 1 does not complete. Because the test needs to be continued until it is confirmed that the emergency generator 1 generates power of at least one-third (34 kW) of the power generation capacity of 100 W.

More specifically, when the charging of the capacitor secondary battery charging elements 3 is completed, the changeover switch 2 is switched to the side of a second switch 15, so that the connection for transmitting three-phase AC power of the emergency generator 1 during the power generation test is switched to the side of the conventional dry-type load resistor 6 for three-phase alternating current.

That is, the load test of the AC power generated at the emergency generator 1 can be continued with the AC load resistor 6 using a conventional rod-shaped resistor unit.

Here, while the load test is continued with the emergency generator 1 being connected to the AC load resistor 6, replacing work of capacitor secondary battery charging element 3 is performed in which the fully-charged capacitor secondary battery charging elements 3 are replaced with capacitor secondary battery charging elements 3 that are not yet charged.

After the replacement, the changeover switch 2 is switched again to the side of the capacitor secondary battery charging elements 3, and the load test is continued.

As described above, the capacitor secondary battery charging elements 3 do not need to be cooled with a cooling fan because the amount of heat generated by the capacitor secondary battery charging elements 3 during charging is extremely small.

Therefore, the weight of the load test system itself can be greatly reduced. The capacitor battery unit 14 having specifications of 4 V, 1 A/h has a weight of approximately 100 g to 200 g, and even though 40 capacitor battery units 14 are used, the total weight thereof is in the range of approximately 4 kg to 8 kg.

Then, various usage of the charged capacitor secondary battery 3 is considered.

The load test system of the present invention can also be used in a load test for a general power supply PS such as an uninterruptible power supply (UPS).

Further, the load test may also be performed in a thermal or nuclear power generator during shut-down to be used in case of an emergency. Further, as the other power supplies to perform the load test, a wind power generator, a solar panel (solar power generator), or the like may be used.

A reference numeral 16 indicates a control unit. Here, the control unit 16 controls transmission of the generated power from the power input section 7 of the emergency generator 1; charging of the capacitor secondary battery charging elements 3, the quick charger 17, or the like; and switching of the connection to the load resistor load resistor 6. Also, the control unit 16 detects fully charged states of the capacitor secondary battery charging elements 3 and the amount of generated power of approximately one third of the capacity of the emergency generator 1.

The control unit 16 controls operation of the changeover switch 2 and the like, and allows selection of the side of the capacitor secondary battery charging elements 3 as major connection control, as well as controls changing of the connection conditions of the capacitor secondary battery charging elements 3 thus selected, and is configured such that the charging voltage and the charging current correspond to the specifications of the charging voltage and charging current of the capacitor secondary battery charging elements 3.

These charging voltage and charging current are set to values or near values suitable for charging of the capacitor secondary battery charging elements 3 that are incorporated with their serial and/or parallel connections being changed.

The quick charger 17 and the battery charging element 20 connected thereto are used for quick charging as needed and also used as auxiliary batteries. In addition to the quick charger 17, the capacitor secondary battery charging elements 3 already charged can also be used as auxiliary batteries.

Conventionally, to drive the load test system, the operating power sources 23, 27 therein have been supplied from a commercial power source on site or secured by preparing a portable power generation apparatus.

However, their connections and preparation for setup have been extremely time consuming. Therefore, as described above, the charged power, for example, the power of the battery charging element 20 or the capacitor battery charging elements 3, can be used as the operation power.

By providing a battery charging element serving as a chargeable power storage section in the load resistor 6, the load test can also be continued without turning off the operating power source even for an instant during the load test.

For example, at an instantaneous power loss, an emergency power source, with the load resistor 6 mounted therein or as the charged auxiliary power source described above, immediately starts a cooling fan to cool the rod-shaped resistor unit (for 1 to 2 minutes). Then, the load test system is immediately stopped.

Thus, by placing the operating power sources 23, 27 in the load test system, there is no need to supply power from a commercial power source on site or to secure power by preparing a portable power generation apparatus.

Next, the action of the load test system according to the present invention will be described.

The load test system is used being mounted in a vehicle so as to be moved to a place or in a building where the emergency generator 1 is placed. It may, however, be used being placed as a stationary type system.

With the load test system of the present invention, for example, a load test of the emergency generator 1 is periodically performed. In the load test, the storage battery 24 or the capacitor secondary battery charging elements 3 of the first embodiment is/are preferentially charged with the power from the emergency generator 1.

At this time, a cooling fan is not required. This is because the electrical resistance therein is small as described above. Therefore, the system can be significantly reduced in weight.

Conventionally, power supplied from the emergency generator 1 has been merely consumed as thermal energy at only the load resistor 6 formed with the rod-shaped resistor. In contrast to this, according to the present invention, power supplied in the load test of the emergency generator 1 is charged and stored in the storage battery 24 and the capacitor secondary battery charging elements 3, so that the supplied power is not consumed wastefully. The charged power can be used as, for example, a battery for an electric vehicle (EV) or a power supply in a building such as a residential building, thus resulting in effective use of the power.

That is, when the specifications of the power charged in the storage battery 24 and the capacitor secondary battery charging elements 3 are set to the same specifications as those of the battery for an electric vehicle (EV), the charged power can be easily used as the battery for EV and the like. It can also be used as a power supply in a building such as a residential building.

Further, the load test system of the present invention can be simply used as a charger when the load test is not performed.

That is, surplus power produced in use state of a solar panel, an electric device, and loads of an electronic device or the like is charged in the capacitor secondary battery charging elements 3 using the load test system as a charging apparatus, so that wasteful energy consumption of the surplus power can be prevented.

An example is given in which the load test system of the present invention is provided with three capacitor secondary battery charging elements 3 corresponding to R phase, S phase, and T phase in order to support the three-phase AC power source. However, in the case of a single phase AC power source or a DC power source, one of R phase, S phase, and T phase may be used.

Next, for example, when the load test system according to the present invention is installed in a vehicle such as a truck and then moved, the use state of the present invention will be described.

This is when a truck of a vehicle provided with front wheels (wheels) and rear wheels (wheels) that can be driven by a wheel driving motor is used, and the vehicle is an electric vehicle (EV).

Such configuration has a merit that a power source of the vehicle can be charged while a load test is performed.

That is, power can also be supplied to loads (including, for example, an air-conditioning device, a meter, a lump, and a driving motor) in the vehicle.

Here, a quick charging power source for a high-performance battery in the electric vehicle which is equipped with the load test system according to the present invention and is moved to a place where a power generation test of the emergency generator 1 is performed will be described.

The quick-charging power source of the automobile equipped with a load test system for 100 kW has a capacity of approximately 200 V, 50 kW in three-phase, which is a sufficient load capacity. Therefore, using stored power in the present invention can significantly save energy, thereby greatly contributing to CO₂ reduction.

Third Embodiment

FIG. 3 illustrates an example of an arrangement of a third embodiment according to the present invention.

This embodiment is an example of the arrangement in which the emergency generator 1 is capable of outputting power generated by a load test to the capacitor secondary battery charging elements 3, to the storage battery 24 such as a lithium ion battery via the chargers 21 having the AC/DC conversion function, to the conventional dry-type load resistor 6, or to a battery 29 of an EV 31 via the quick charger 17, and the emergency generator 1 is also capable of collectively outputting the power to some of these, to thereby perform a load test.

In FIG. 3, three capacitor secondary battery charging elements 3 in which AC power generated from the emergency generator 1 is converted into DC power to be inputted are connected to the emergency generator 1 via an overall changeover switch unit 30.

Therefore, the AC/DC converter 4 is interposed between the emergency generator 1 and the three capacitor secondary battery charging elements 3, and converts AC into DC to transmit the DC power to the side of the three capacitor secondary battery charging elements 3.

The DC power converted by the AC/DC converter 4 is supplied to the three capacitor secondary battery charging elements 3 that are connected to the AC/DC converter 4. Then, the three capacitor secondary battery charging elements 3 charge and store a generated power to be used in an operation test, that is, a load test, of the emergency generator 1 without wasting the generated power.

Switch sections 18 are provided on the input side of the three capacitor secondary battery charging elements 3, and the three-phase alternating current is connected per phase to each of the secondary battery charging elements 3 via the corresponding switch sections 18.

Further, for example, in the case where the charging times of the three capacitor secondary battery charging elements 3 are slightly different from one another, the corresponding switch section 18 is opened/closed to allow the three secondary battery charging elements 3 to be individually attached/detached. These switch sections 18 are configured as a changeover switch unit 19 to perform the switching control by the control unit 16.

Here, as described above, the capacitor secondary battery charging elements 3 cannot be formed by connecting a plurality of lithium ion batteries in serial or in parallel. When a plurality of lithium ion batteries are used in serial or parallel connection, high heat is generated to thereby increase the possibility of igniting the batteries. Moreover, when the lithium ion batteries are connected in serial or in parallel, it is difficult to adjust the lithium ion batteries, such as maintaining voltage balance of the respective lithium ion batteries. Therefore, in order to prevent it, a complicated protection circuit needs to be formed.

Therefore, after completion of charging, once the secondary battery charging elements 3 thus interrelated are disconnected from the connecting, the circuits in the secondary battery charging elements 3 formed of lithium ion batteries need to be reestablished. That is, it is necessary to perform adjustment such as voltage adjustment again. Therefore, it is not suitable to use lithium ion batteries for the formation of the secondary battery charging elements.

As a battery for the secondary battery, a dry battery using nickel or the like is generally available. Although it is considered that a large number of the dry batteries are disposed to form the secondary battery charging elements, the dry battery for the secondary battery has a small capacity and is heavy in weight relative to the capacity. Therefore, it is also not suitable for the present invention to use the dry battery for the secondary battery.

Thus, it is considered that a secondary battery using a capacitor is used to form the capacitor secondary battery charging element 3. Currently, a secondary battery using a capacitor has been developed as much as possible, and the secondary battery charging element 3 formed using the capacitor can be easily connected in serial or in parallel when a large capacity circuit of the secondary battery charging element 3 is established, and no complicated protection circuit is required. In addition, there is little possibility of igniting the secondary battery charging element 3. Further, after charging of the secondary battery charging elements 3 is completed, the secondary battery charging elements 3 are detached from the load test system and new capacitor secondary battery charging elements 3 are then connected. Even so, it is not necessary to perform adjustment, so-called voltage adjustment, like the secondary battery charging element formed with lithium ion batteries.

As described above, to provide explanation of the secondary battery using a capacitor, for example, a capacitor battery uses an electric double layer state as a replacement of a dielectric, the state being formed on interfaces between the electrodes 9, 10 having a square flat shape and the electrolytic solution 11.

Usually, an electric double layer capacitor includes the positive electrode 9, the negative electrode 10, the electrolytic solution 11, and the separator 12 for preventing short-circuit of the electrodes opposed to each other. Further, the exterior thereof is covered with the covering material 13 formed of resin film or the like, and the capacitor battery unit 14 having, for example, specifications of 4 V, 1 A/h and a generally square, flat shape is formed (see FIG. 4).

The size thereof is approximately 100 cm in width, approximately 70 cm in length, and in the range of approximately 2 cm to 3 cm in thickness, and the weight thereof is approximately in the range of 100 g to 200 g.

Then, a plurality of the capacitor battery units 14, for example, approximately 40 capacitor battery units 14 are connected in series to form a capacitor secondary battery charging element 3 having a capacity of approximately 8 kWh.

Moreover, the secondary battery 3 using this capacitor generates extremely small amount of heat, and does not require a complicated protection circuit to be disposed when connected in series or in parallel.

Thus, the secondary battery 3 using a capacitor can be formed as the capacitor secondary battery charging element 3 having a capacity of approximately 8 kWh by connecting the plurality of the capacitor battery units 14 in series without separately requiring a protection circuit.

The capacitor secondary battery charging element 3 is formed so as to have a charging capacity of 8 kWh as a whole, but not limited thereto. The capacitor secondary battery charging element 3 having a charging capacity flexibly changed can be formed by changing several of the capacitor battery units 14 and connecting them in series or in parallel.

In FIG. 3, three capacitor secondary battery charging elements 3 are connected in which the capacitor battery units 14 based on the above-mentioned specifications are connected as described above.

Here, when the emergency generator 1 is driven, AC power at a voltage of 200 Vis generated from the emergency generator 1. Then, the generated AC power is converted from AC to DC by the AC/DC converter 4 that is connected to the side where three-phase AC power is transmitted, and the capacitor secondary battery charging elements 3 connected to the AC/DC converter 4 are charged with the DC power. Thus, a load test of the emergency generator 1 is performed, and the generated power can be charged and stored in the capacitor secondary battery charging elements 3 without wasting the generated power.

Here, the secondary battery using a capacitor is almost instantaneously charged and has an extremely small internal resistance, so that the amount of heat generated by electrical resistance is extremely small. For example, at approximately one hour after starting of the load test, each of the capacitor secondary battery charging elements 3 reaches a fully charged state. One capacitor secondary battery charging element 3 having a capacity of 8 kWh, and three capacitor secondary battery charging elements 3 having a total capacity of 24 kWh are charged with DC power, which is stored.

When the three capacitor secondary battery charging elements 3 reach fully charged states, the detector 5 for detecting full charge that is connected to the side of the capacitor secondary battery charging elements 3 detects their fully charged states and then reports the detection with an alarm signal. It should be noted that the alarm signal includes sound, light, and the like.

However, in this embodiment, power receiving from the power generated by the load test of the emergency generator 1 is not performed only by charging of the capacitor secondary battery charging elements 3.

That is, in addition to the load test by the charging of the capacitor secondary battery charging elements 3, other power receiving can also be performed.

That is, the overall changeover switch unit 30 is switched, so that the connection for transmitting three-phase AC power of the emergency generator 1 during the power generation test is switched to the side of the plurality of chargers 21 . . . having the AC/DC conversion function that are connected in parallel, and the storage battery 24 is charged.

In the present invention, when the load test is performed, the control unit 16 can optionally determine whether either of the units, that is, either the capacitor secondary batteries 3 or the storage battery 24 is/are preferentially charged. The capacitor secondary battery charging elements 3 or the storage battery 24 may be charged first. The control unit 16 can be set according to the site situation for the load test or the state of the emergency generator 1 on site.

As understood from FIG. 3, DC power from another power generation apparatus 22 such as a solar panel may also be connected in parallel to the output side together with the plurality of chargers 21 . . . having the AC/DC conversion function, and the power from this power generation apparatus 22 can also be charged.

In addition, it is configured that connections are established between the emergency generator 1 and the plurality of chargers 21 . . . having the AC/DC conversion function that are connected in parallel via the capacity changing switches 25, and the charging capacity to the storage battery 24 can be changed by switching the capacity changing switches 25.

A reference numeral 23 indicates the operating power source for driving the emergency generator 1.

Here, AC power generated from the emergency generator 1 is inputted to the plurality of chargers 21 having the AC/DC conversion function that are connected in parallel, or five chargers 21 having the AC/DC conversion function in this embodiment.

Then, the AC power inputted to the plurality of chargers 21 having the AC/DC conversion function of which each charging capacity is set to, for example, 4 kW is converted into DC and is transmitted to the side of a storage battery 24 such as a lithium ion battery at a predetermined output voltage, for example, an output voltage set to 48 V, to thereby be inputted.

Here, the input voltage of the storage battery 24 is set to substantially the same voltage as the above-mentioned output voltage of the plurality of chargers 21 having the AC/DC conversion function that are connected in parallel, or to a voltage lower than the above-mentioned output voltage, and the charging capacity thereof is set to approximately 18 kW or 36 kW.

Therefore, the AC power generated at the emergency generator 1 is converted into DC by the chargers 21 having the AC/DC conversion function and is transmitted to the side of the storage battery 24 to be charged.

Here, in the conventional load test, all the power generated by the emergency generator 1 has been consumed as thermal energy. In the present invention, however, the generated power can be effectively used.

More specifically, the plurality of chargers 21 having the AC/DC conversion function allow the AC power tentatively generated for the load test of the emergency generator 1 to be charged in the storage battery 24. When this storage battery 24 has a power capacity of, for example, 18 kW or 36 kW, it can be completely charged in approximately 30 minutes to 1 hour by the above-mentioned load test.

Further, as shown in FIG. 3, the DC/AC converter 26 is connected to the output side of the storage battery 24, and operation power, for example, power for driving the cooling fan to cool the hot resistor, can be supplied to the operating power source 27 of the load resistor 6 via the DC/AC converter 26. In addition, the operation power is also configured to allow to be supplied to the above-mentioned operating power source 23 of the emergency generator 1. It should be noted that the operating power source 23 may be able to obtain power from an external power source such as a commercial power source.

In FIG. 3, it is configured that the generated power from the emergency generator 1 can also be transmitted to the conventional-type load resistor 6 to perform the load test. Therefore, for example, after charging of the storage battery 24 is completed, the overall changeover switch unit 30 is temporarily switched, and the load test may be performed using the conventional-type load resistor 6.

In addition, the quick charger 17 is also connected to the overall changeover switch unit 30, and the battery 29 of the EV 31 can be charged via the quick charger 17.

Here, the EV 31 is equipped with the components of this embodiment and then transports them to a site where a load test is performed. Therefore, the EV 31 is charged with the power generated by the load test on site, and can make full use of such generated power without any waste.

Then, the battery 29 of this EV 31 can also be charged via a normal charger 33, and after the load test is finished, it can be gradually charged through the normal charger 33 from the storage battery 24 installed in the EV 31 in a garage.

There are circumstances such that at the time of a great earthquake, an emergency power generation apparatus did not start due to external power loss, failing to operate a nuclear-power plant, which resulted in a great disaster. There are over 200,000 emergency power generation apparatuses, large and small, in familiar infrastructure facilities, hospitals, and commercial buildings, and a hybrid type emergency power generation apparatus as in the present invention is required which has operating power in combination with an emergency power generation apparatus requiring no external power.

The emergency power source is reviewed, and periodically operated under loaded conditions every three or four months at nuclear-power plants. Although a water resistor is placed in a pump station and the like, it is not used because arc discharge can be dangerous, and a dry-type load device is prepared to perform a load operation with one-third or more of the power generation capacity.

According to the present invention, however, once the device starts to be operated, it does not use any external power, and may become the same system as used at an independent space station.

Here, referring to a power storage load device, power obtained in the load test of the emergency generator is stored. For storage, electrolysis is performed and the generated hydrogen may be stored as organic hydride.

As described above, the power may be stored by a storage battery, a fuel battery, a capacitor secondary battery, LiB, or the like. There is an excellent effect that the stored power can be used in place of external power.

Further, externally generated power such as solar power is also adapted to be stored in the storage battery, the fuel battery, the capacitor secondary battery, LiB, or the like.

It is important to select the storage battery, fuel battery, capacitor secondary battery, LiB, and the like with good balance so as to perform an optimum load test using individual storage battery, fuel battery, capacitor secondary battery, LiB, or the like as optimum loads to the emergency generator.

REFERENCE SIGNS LIST

-   1 Emergency generator -   2 Changeover switch -   3 Capacitor secondary battery charging element -   4 AC/DC converter -   5 Detector -   6 Load resistor -   7 Power input section -   8 First switch section -   9 Positive electrode -   10 Negative electrode -   11 Electrolytic solution -   12 Separator -   13 Covering material -   14 Capacitor battery unit -   15 Second switch -   16 Control unit -   17 Emergency charger -   18 Switch section -   19 Changeover switch unit -   20 Battery charging element -   21 Charger having an AC/DC conversion function -   22 Another power generation apparatus -   23 Operating power source of emergency generator -   24 Storage battery -   25 Capacity changing switch -   26 DC/AC converter -   27 Operating power source -   28 Operating power source changeover switch -   29 Battery -   30 Overall changeover switch unit -   31 Electric vehicle -   33 Normal charger 

The invention claimed is:
 1. A load test system for performing a load test of a generator, the load test system comprising: a plurality of chargers having an AC/DC conversion function being connected in parallel, to which AC power generated from the generator is inputted; one storage battery to which AC power inputted to the plurality of chargers having the AC/DC conversion function being connected in parallel is converted into DC power of a predetermined output voltage and then inputted; and a plurality of capacity changing switches connected to the plurality of chargers, respectively, wherein the plurality of chargers having the AC/DC conversion function are connected to the one storage battery; and charging capacity for adjusting load is changed by switching the capacity changing switches.
 2. The load test system according to claim 1, the load test system further comprising: a load resistor to which AC power generated from the generator is inputted, wherein the load resistor has a dry-type resistor unit for converting the inputted AC power into thermal energy, and after full charging of the one storage battery is completed, AC power generated from the generator is inputted to the load resistor.
 3. The load test system according to claim 1, the load test system further comprising: a DC/AC converter for converting DC power from the one storage battery into AC power; and an operating power source of a load resistor to which AC power converted by the DC/AC converter is inputted, wherein the load resistor has a dry-type resistor unit for converting the inputted AC power into thermal energy, and at an instantaneous power loss, power charged in the load test system is supplied to a cooling fan of the load resistor via the operating power source of the load resistor, then the load test system is stopped.
 4. The load test system according to claim 3, the load test system further comprising: an operating power source for driving a generator; and an operating power source changeover switch, wherein power charged in the load test system is supplied to the operating power source of the generator or the operating power source of the load resistor, by switching the operating power source change over switch.
 5. The load test system according to claim 1, the load test system further comprising: a changeover switch to which AC power from the generator is inputted; an AC/DC converter being connected to a first switch section of the changeover switch, to which AC power generated from the generator is inputted; a plurality of secondary battery charging elements to which DC power converted by the AC/DC converter is supplied; and a load resistor being switched to be connected to a second switch section of the changeover switch, to which AC power from the generator is inputted to convert the AC power into thermal energy, wherein the secondary battery charging elements are formed by connecting a plurality of secondary batteries in series and/or in parallel, and are able to correspond to plural kinds of generators having different power generation capacities.
 6. The load test system according to claim 5, wherein the generator is a three-phase alternating current generator; and the plurality of secondary batteries have a generally square shape, a size of approximately 100 cm in width, approximately 70 cm in length, a thickness in a range of approximately 2 cm to 4 cm, and a weight in a range of approximately 100 g to 300 g.
 7. The load test system according to claim 1, the load test system further comprising: a changeover switch to which AC power from the generator is supplied via a power input section; an AC/DC converter being connected to a first switch section of the changeover switch, to which AC power from the generator is inputted; a plurality of secondary battery charging elements to which DC power converted by the AC/DC converter is inputted; and a load resistor being switched to be connected to a second switch section of the changeover switch and being formed with a dry-type resistor unit for converting the inputted AC power into thermal energy, wherein the generator is a three-phase alternating current generator; and the secondary battery charging elements are formed by connecting a plurality of capacitor secondary batteries in series and/or in parallel, and are able to correspond to plural kinds of three-phase alternating current generators having different power generation capacities.
 8. The load test system according to claim 1, wherein the chargers having the AC/DC conversion function and the storage battery can be installed in an electric vehicle, and a power source of the electric vehicle can be inputted from the charged storage battery.
 9. The load test system according to claim 5, wherein the secondary battery charging elements can be installed in an electric vehicle, and a power source of the electric vehicle can be inputted from the charged secondary battery charging elements.
 10. The load test system according to claim 3, wherein the operating power source at a time of driving the load resistor is based on power charged in the load test system.
 11. The load test system according to claim 4, wherein the operating power source at a time of driving the generator is based on power charged in the load test system. 